Guzzanti is very rare and comes from the Catania area, Guzzetti has a large stock in Lombardy in the Varese, Como and Milanese areas, with a significant stock also in the Catanzaro area. Guzzetto, absolutely rare, is specific to Catanzaro, Guzzi is probably from two areas, the Crotone and Catanzaro and western Lombardy, Guzzini has a stock in Bologna and one in Ancona and above all in Recanati in the Macerata area, Guzzino, very rare, it would seem of the Palermo, in particular Caccamo, Guzzo seems to have at least three nuclei, one in western Sicily, one in Calabria, Cosenza and Catanzaro, and one in Veneto, perhaps it also has a strain between the Varese area and the Novara area, Guzzon seems specific to the area between Padua and Venice. All these surnames should derive, directly or through hypocoristic or augmentative, even dialectal, modifications from the late medieval name Gutius.
Lo Guzzo is typically Sicilian, specific to Mazzarino in Nissen, has a very small stock in Nicosia in the Enna area and Catania, it should derive from a nickname based on the Sicilian dialect word guzzu (rabid little dog, snarling hatch), probably to emphasize an aspect of the character of the progenitor.
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